Telephone-switch



(No Model.) 7

A. STROMBERG & A. GARLSON.

TELEPHONE SWITCH.

Patented June 19, 1894.

N IQNAL LITHOGIAMM MPANY.

NINGYUN, a,

I UNITED STATES- PATENT Fines,

ALFRED STROM'BERG AND ANDREW CARLSON, OF CHICAGO, ILLINOIS TELEPHONE-SWITCH.

SPECIFICATION forming part of Letters Patent No. 521,514, dated Jime 19, 1894.

Applicatlonfiled January 26,1894. serial No. 498,136. (No model.)

To all whom it may concern.-

Be it known that we, ALFRED STROMBERG and ANDREW CARLsON, citizens of the Unitedfollowing is a full, clear, concise, and exact receiver embodying our invention. a partial sectional view at right angles theredescription, reference being had to the accompanying drawings, forming a part of this specification.

Our invention relates to telephone switches, and its object is to provide a switch conveniently located for use by the person using the telephone. 7 I

Our invention in its preferred form comprises a switch located upon the receiver, or hand telephone, in position conveniently to be closed by the hand of the person holding the telephone to his ear. The switch may serve to open and close the circuit through the subscribers bell and generator, the primary circuit of his induction coil, or for any other desired purpose.

We will describe our invention more in detail in connection with the accompanying drawings, in which Figure 1 is a sectional view of a telephone Fig. 2 is to. Fig. 3 is a sectional view on line 3 3, Fig. 2. Fig. t is a diagrammatic view-illustrating the circuit connections when the switch is used for cutting the telephone out of circuit.

Like letters refer to like parts in the several figures.

Upon the interior of the casing roof the receiver is secured by one end a strip of metal I) provided upon its free end with arms 1) 19 The arm I) normally rests against a contact 0, being yieldingly held against the same by the spring at resting against the face of strip 17. The spring d and strip 6 are secured in position by screws e e. Opposite the arm 19 and normally out of contact therewith is provided a second contact 0', against which said arm 6 may be caused to bear by the depression of button f which rests against the end of strip 19. The depression of the button also serves to break the contact between the arm I) and contact 0. Three binding posts h h h are shown upon the end of the receiver, one

of which, h, is electrically connected with the strip b which serves as the movable element of the switch, the other binding posts h h being connected respectively with the contacts c c. As shown in Fig. 4c the telephone coil is may be included in circuit between contact c and binding post h while the contact 0 may be connected through binding post h with the branch containing the bell Z and generator m. The strip I) normally rests against contact 0 so that circuit is closed through the circuit containing the bell and generator when the telephone is not in use.

When it is desired to use the telephone the button f is depressed by the thumb as the receiver is held in the hand, the circuit through the. bell and generator circuit being thus opened, while circuit is closed through the telephone set.

The switch instead of being located at the transmitter end of the instrument may be placed in any other convenient location, but we preferably locate the switch at the transmitter end as the push button may thus be readily engaged by the thumb of the hand holding the telephone and depressed without conscious effort.

Instead of employing the switch for alternately including in circuit the calling apparatus and the telephone set, it is evident that the switch may be used for other purposes, as for instance, to open and close the primary circuit of the transmitter induction coil, our invention being capable of numerous adaptations. We do not, therefore, desire-to limit ourselves to details of construction, but

We claim as new and desire to secure by Letters Patent-- 1. The combination with a hand telephone,

telephone set may be placed in circuit by the ing connected with the binding post connected with said movable contact element,

the other two binding posts being connected I5 by parallel branches with the opposite side of the line, and calling apparatus located in the branch that is not in circuit with the telephone coil, substantially as described.

In witness whereof We hereunto subscribe 20 our names this 24th day of January, A. D. 1894.

ALFRED STRQMBERG. ANDREW CARLSON. Witnesses:

W. CLYDE JONES, GEORGE L. Cane G. 

